1. Field of the Invention
The present invention relates to single-component organopolysiloxane compositions which are storage stable in the absence of moisture, harden or cure to elastomers beginning at room temperature in the presence of moisture and are microorganism resistant by virtue of incorporation therein of a particularly active fungicidal agent.
2. Description of the Prior Art
Single-component organopolysiloxane compositions have been in use for over 20 years as sealing materials in all fields of application which require resilient seals which efficiently withstand aging, inclement weather, heat and cold and the action of corrosive materials. In particular, in the field of sanitation they provide the sealing of the chinks present in bathrooms and kitchens, around baths, showers, sinks, tiling and the like. However, these seals very quickly lose their new attractive appearance as a result of the proliferation, on their surfaces, of molds which form dark-colored, unattractive areas and streaks.
Fungicidal agents have been introduced into organopolysiloxane compositions to resist the development of such microorganisms. However, not all of the known fungicidal agents commonly employed in agriculture or in the field of paints and coatings are suitable; in fact, their presence can have an undesirable effect, for example, on the stability of the compositions or on the adhesion of the elastomers produced by these compositions to various substrates (compare published European Application No. 34,877).
It is thus necessary to compromise when attempting to reconcile high antifungal effectiveness and the retention of good physical properties. This is precisely why numerous documents have been published and continue to be published on the subject of addition of antifungal compounds to organopolysiloxane compositions and elastomers.
Among the antifungal compounds described in the literature, exemplary are:
(1) 2-(4-Thiazolyl)benzimidazole (published French Application No. 2,421,195); PA1 (2) Iodoalkylphenylsulfones (aforementioned European Application No. 34,877) PA1 (3) Phenylmercury salts of carboxylic acids (French Pat. No. 1,462,754); PA1 (4) 2,3,5,6-Tetrachloro-4-methylsulfonylpyridine (published Japanese Application No. 76/106,158); PA1 (5) Oxides and other derivatives of triorganotin compounds (published Japanese Application Nos. 82/096,044 and 82/133,150). PA1 (A) 100 parts by weight of an .alpha.,.omega.-dihydroxydiorganopolysiloxane polymer, having a viscosity of 700 to 1,000,000 mPa.s at 25.degree. C., comprising recurring siloxy units of the formula R.sub.2 SiO in which the symbols R, which may be identical or different, denote hydrocarbon radicals containing from 1 to 8 carbon atoms, substituted or unsubstituted by halogen atoms or cyano groups; PA1 (B) 2 to 25 parts by weight of an organosilane of the formula R.sub.a Si(Z).sub.4-a in which the symbol R has the meaning given under (A), and the symbols Z, which may be identical or different, denote hydrolyzable radicals selected from among those of the formulae: ##STR1## in which: (i) the symbol R.sup.1 denotes an alkyl radical containing from 1 to 4 carbon atoms, or a .beta.-methoxyethyl radical of the formula --CH.sub.2 CH.sub.2 OCH.sub.3, PA1 (C) 5 to 200 parts by weight of inorganic fillers; and PA1 (D) 0.0003 to 15 parts by weight of a hardening or curing catalyst selected from among iron and titanium chelates, the tin, iron or lead salts of carboxylic acids, organotin salts of carboxylic acids, alkyl titanates and zirconates, or the products of reaction of organotin salts of carboxylic acids with alkyl titanates, which composition comprises from 0.01 to 1.2% by weight, based on the total weight of the composition, of a fungicidal agent (E) comprising at least one tetraalkylthiuram disulfide having the formla (I): ##STR2## in which the radicals Y, which may be identical or different, denote an alkyl radical containing from 1 to 4 carbon atoms. PA1 (a) alkyl and haloalkyl radicals containing from 1 to 8 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, n-hexyl, 2-ethylhexyl, n-octyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, and 4,4,4-3,3-pentafluorobutyl radicals; PA1 (b) cycloalkyl and halocycloalkyl radicals containing from 4 to 8 carbon atoms, such as cyclopentyl, cyclohexyl, methylcyclohexyl, 2,3-difluorocyclobutyl, and 3,4-diflouro-5-methylcycloheptyl radicals; PA1 (c) alkenyl radicals containing from 2 to 4 carbon atoms such as vinyl, allyl and 2-butenyl radicals, PA1 (d) aryl and haloaryl radicals containing from 6 to 8 carbon atoms such as phenyl, tolyl, xylyl, chlorophenyl, dichlorophenyl and trichlorophenyl radicals, and PA1 (e) cyanoalkyl radicals, the alkyl moieties of which contain from 2 to 3 carbon atoms, such as .beta.-cyanoethyl and .gamma.-cyanopropyl radicals. PA1 (1) alkyl radicals containing from 1 to 15 carbon atoms, such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, 1-ethylpentyl, n-hexyl, n-octyl, neodecyl, n-decyl, n-dodecyl and n-pentadecyl radicals; PA1 (2) cycloalkyl radicals containing from 5 to 6 ring carbon atoms, such as cyclopentyl and cyclohexyl radicals; and PA1 (3) aryl radicals containing from 6 to 8 carbon atoms, such as phenyl, tolyl or xylyl radicals. PA1 (1) alkyl radicals containing from 1 to 10 carbon atoms, such as methyl, ethyl, n-propyl, n-butyl, n-hexyl, 1-ethylpentyl, n-octyl or n-decyl radicals; PA1 (2) cycloalkyl radicals containing from 5 to 8 carbon atoms, such as cyclopentyl, cyclohexyl, methylcyclohexyl or dimethylcyclohexyl radicals; PA1 (3) aryl radicals containing from 6 to 8 carbon atoms, such as phenyl, tolyl or xylyl radicals. PA1 (i) iron or titanium chelates, such as those of the formulae (the chelate bonds are not shown): ##STR9## PA1 (2i) tin, iron or lead salts of carboxylic acids, such as tin, iron or lead 2-ethylhexanoate, stearate, oleate or naphthenate; PA1 (3i) organotin salts of carboxylic acids, such as di(n-butyl)tin diacetate and dilaurate, di(n-octyl)tin diacetate and dilaurate, dimethyltin di(2-ethylhexanoate), di(n-butyl)tin diversatate, di(n-octyl)tin succinate or di(n-octyl)tin maleate; PA1 (4i) alkyl titanates and zirconates, such as those of the formulae: PA1 (n-C.sub.4 H.sub.9 O).sub.4 Ti, (C.sub.2 H.sub.5 O).sub.4 Ti, [(CH.sub.3).sub.2 CHO].sub.4 Ti (n-C.sub.3 H.sub.7 O).sub.4 Ti, (n-C.sub.8 H.sub.17 O).sub.4 Ti, (CH.sub.3 OCH.sub.2 CH.sub.2 O).sub.4 Ti [CH.sub.3 (CH.sub.2).sub.3 CH(C.sub.2 H.sub.5)CH.sub.2 O].sub.4 Ti, (C.sub.2 H.sub.5 O).sub.4 Zr, [(CH.sub.3).sub.2 CHO].sub.4 Zr, (n-C.sub.3 H.sub.7 O).sub.4 Zr (n-C.sub.4 H.sub.9 O).sub.4 Zr, [(CH.sub.3).sub.3 C--O].sub.4 Zr, (CH.sub.3 OCH.sub.2 CH.sub.2 O).sub.4 Zr (n-C.sub.7 H.sub.15 O).sub.4 Zr; PA1 (5i) products of reaction of organotin salts of carboxylic acids (3i) with alkyl titanates (4i). These compounds contain Ti--O--Sn bonds; their preparation is described in French Pat. No. 1,392,648 and British Pat. No. 928,946. PA1 (i) the symbol R.sup.6 denotes a methyl or ethyl radical; PA1 (ii) the symbol G denotes an alkylene radical containing from 1 to 5 carbon atoms; PA1 (iii) the symbol X denotes an oxygen or sulfur atom; PA1 (iv) the G' denotes an alkylene radical containing from 2 to 5 carbon atoms; PA1 (v) the symbol Y denotes a radical of the formula --(G"NH).sub.k R.sup.7 in which the symbol G" denotes an alkylene radical containing from 2 to 6 carbon atoms; the symbol R.sup.7 denotes a hydrogen atom or an alkyl radical containing from 1 to 4 carbon atoms, and the symbol k denotes zero, 1, 2 or 3; PA1 (vi) the symbol Y' denotes a methyl, vinyl or phenyl radical; PA1 (vii) the symbols p and n denote zero or 1; when p denotes 1 the symbol R.sup.6 denotes only a methyl radical; and PA1 (viii) the symbol m denotes zero, 1 or 2. PA1 H.sub.2 N(CH.sub.2).sub.3 Si(OCH.sub.2 CH.sub.2 OCH.sub.3).sub.3, H.sub.2 N(CH.sub.2).sub.3 Si(OC.sub.2 H.sub.5).sub.3 H.sub.2 N(CH.sub.2).sub.3 Si(OCH.sub.3).sub.3, HN(C.sub.2 H.sub.5)CH.sub.2 Si(OCH.sub.3).sub.3 H.sub.2 N(CH.sub.2).sub.2 NH(CH.sub.2).sub.3 Si(OCH.sub.3).sub.3, H.sub.2 N(CH.sub.2).sub.2 NH(CH.sub.2).sub.3 Si(OCH.sub.2 CH.sub.2 OCH.sub.3).sub.3, H(NHCH.sub.2 CH.sub.2).sub.2 NH(CH.sub.2).sub.3 SiCH.sub.3 (OCH.sub.3).sub.2. PA1 H.sub.2 N(CH.sub.2).sub.3 O(CH.sub.2).sub.3 Si(OCH.sub.2 CH.sub.2 OCH.sub.3).sub.3, HN(CH.sub.3)(CH.sub.2).sub.3 O(CH.sub.2).sub.3 Si(OCH.sub.3).sub.3, H.sub.2 N(CH.sub.2).sub.2 S(CH.sub.2).sub.3 Si(OCH.sub.3).sub.3, H(NHCH.sub.2 CH.sub.2).sub.2 S(CH.sub.2).sub.3 SiCH.sub.3 (OCH.sub.3).sub.2. PA1 (1) .alpha.-.omega.-bis(triorganosiloxy)diorganopolysiloxane polymers having a viscosity of at least 10 mPa.multidot.s at 25.degree. C. in which the organic radicals bonded to the silicon atoms are selected from methyl, vinyl or phenyl radicals; .alpha.,.omega.-bis(trimethylsiloxy)dimethylpolysiloxane oils having a viscosity of 10 mPa.multidot.s at 25.degree. C. to 1,000 mPa.multidot.s at 25.degree. C., are preferably incorporated; PA1 (2) branched, liquid methylpolysiloxane polymers containing from 0.1 to 8% of hydroxyl groups bonded to the silicon atoms, comprising (CH.sub.3).sub.3 Si.sub.0.5,(CH.sub.3).sub.2 SiO, and CH.sub.3 SiO.sub.1.5 units distributed such as to provide a (CH.sub.3).sub.3 SiO.sub.0.5 /(CH.sub.3).sub.2 SiO ratio of 0.01 to 0.15 and a CH.sub.3 SiO.sub.1.5 /(CH.sub.3).sub.2 SiO ratio of 0.1 to 1.5; PA1 (3) .alpha.,.omega.-dihydroxydimethylpolysiloxane oils having a viscosity of 10 to 300 mPa.multidot.s at 25.degree. C. and .alpha.,.omega.-dihydroxymethylphenylpolysiloxane oils having a viscosity of 200 to 600 mPa.multidot.s at 25.degree. C.; and PA1 (4) diphenylsilanediol or 1,1,3,3-tetramethyldisiloxanediol. PA1 (1) aliphatic, cycloaliphatic, aromatic, halogenated or non-halogenated hydrocarbons, such as n-heptane, n-octane, cyclohexane, methylcyclohexane, toluene, xylene, mesitylene, cumene, tetralin, decalin, perchloroethylene, trichloroethane, tetrachloroethane, chlorobenzene, or orthodichlorobenzene; PA1 (2) aliphatic and cycloaliphatic ketones, such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone or isophorone; and PA1 (3) esters, such as ethyl acetate, butyl acetate or ethyloxyethanol acetate.